Adjustable plate cylinder for printing presses



June 23, 1936. 1- KQPPE ADJUSTABLE PLATE CYLINDER FOR PRINTING PRESSES Filed March 26, 1934 2 Sheets-Sheet l 23 W6. A. T. KOPPE 2,045,151

ADJUSTABLE PLATE CYLINDER FOR PRINTING PRESSES Filed March 26, 1934 2 Sheets-Sheet 2 52 54 M 50 i g6 9 50 illll I M W Patented June 23, 1936 UNITED STATES PATENT OFFICE ADJUSTABLE PLATE CYLINDER FOR PRINTING PRESSES This invention relates to improvements in printing presses and is particularly adapted for that type of press in which an inked impression carried by an offset press plate mounted on a plate cylinder is transferred by a rubber blanket mounted on a transfer cylinder to a paper sheet carried by the rotating paper-carrying cylinder of the press. The principal object of the invention is to provide means for effecting the angular adjustment of the plate cylinder about its axis of rotation in order to vary the position of the printed work on the paper sheet with respect to the edge of the sheet, without changing the position of the plate on the plate cylinder. A further object of the invention is to provide a printing press having a plate carrying cylinder which is adjustable about the shaft on which it is mounted for the purpose of varying the position. of the edges of the plate with reference to a contacting transfer cylinder. Still another object of the invention is to provide an improved clamping mechanism by which a. cylinder of a printing press may be clamped on its shaft and readily adjusted to any desired angular position. Other objects relate to various features of construction and arrangement which will appear more fully hereinafter.

The nature of the invention will be understood from the following specification taken with the accompanying drawings, in which one embodiment is illustrated. In the drawings,

Fig. 1 shows a vertical section transversely to the axes of the cylinders of a printing press of the offset type, showing the improved clamp of the present invention applied to the uppermost cylinder and illustrating in a general way the means by which the paper sheets are fed to the paper-carrying cylinder;

Fig. 2 shows an enlarged section taken axially of the plate carrying cylinder on the line 2-2 of Fig. 1; and

Fig. 3 is a perspective view of the improved clamp by which the plate carrying cylinder is secured upon its shaft.

As illustrated in Fig. 1, the invention is applied to a printing press comprising side frames Ill having mounted between them a plate cylinder H, a transfer cylinder l2, a paper-carrying cylinder l3 and a delivery cylinder H. The plate cylinder II is mounted upon a shaft i5 which is journaled at its ends in bearings carried by the side frames Hi. This cylinder is adapted to carry on its peripheral surface an oflset press plate ii, of zinc or the like, which has one edge secured between clamps l1 and the other edge secured between clamps i8 which are located within a longitudinal recess H formed in the outer cylindrical portion of the cylinder. The press plate I6 is adapted to be inked by inking rollers i9 which are carried by a head 20, pivoted at 2| on the side frames i and adapted to carry an ink supply which is delivered to the rollers l9 through other rollers 22. The cylinder I l rotates in the direction of the arrow 23 and the press plate I0 is adapted to contact with and transfer its inked impression to a rubber blanket 25 which is secured on the surface of the transfer cylinder l2 by means of clamps 26 and 21 which are located within a longitudinal recess i2 formed in the cylinder.

The shaft ill of the plate cylinder II has secured thereon a large gear 28 which meshes with a similar large gear 29 secured upon the shaft 38 which is journaled in the side frames Ill and which carries the transfer cylinder l2. By means of this connection, the cylinder I2 is caused to rotate in the direction of the arrow 3| and the impression carried by the blanket 25 is adapted to be transferred to a paper sheet mounted upon the surface of the cylinder l3 which rotates in the direction of the arrow 32 and which is carried by a shaft 33 journaled in the side frames. The paper sheets, when printed, are removed from the cylinder l3 by clamping devices 34 which are carried by endless chains 35 passing around the delivery cylinder Id. The paper sheets are delivered to the cylinder l3 from a table 36 by means of suitable transfer mechanism which may be of the form described and claimed in my copending application Serial No. 700,258, filed November 29, 1933. This mechanism includes a supporting plate 36 on which the forward portions of the paper sheets are successively brought to rest with the forward edge of each sheet engag ing a series of stops 31 mounted on a shaft 38. When these stops are elevated, the paper sheets are moved by certain suction devices into engagement with the stops 38A which are carried by the cylinder l3, whereupon the gripping fingers 39, carried by the cylinder, are actuated to grip the paper sheet which is then carried around with the cylinder l3 to receive an inked impression from the cylinder l2. The suction devices by which the sheets are moved into engagement with the stops 38A comprise a series of suction drums 40 which rotate with a hollow shaft II, the interior of which is connected with a source of suction. Each drum 40 has a series of apertures in its peripheral portion which are connected with the interior of'the hollow shaft 4| through passages formed in stationary suction blocks 42.

When the stops 3'! are elevated, the suction ex erted through the blocks 42 and the openings formed in the peripheral portions of the drums 40 cause the paper sheets to be positively gripped and moved until their forward edges engage the stops 38A, whereupon the suction is relieved and the paper sheet is released by the drums.

The present invention relates to the means by which the cylinder l l is adjustably secured upon the shaft i5 and this mechanism is more particularly illustrated in Figs. 2 and 3. The cylinder II is rotatably mounted upon the shaft [5 and adjacent one end of the cylinder there is located the gear 28, previously referred to, which is secured against rotation on the shaft by means of a key 45 in addition to being held against endwise movement by means of a set screw 46 which engages a threaded aperture in the hub of the gear and bears against the surface of the shaft. The end of the cylinder II is reduced in diameter as shown at I I and there is fitted upon this reduced portion a bearing ring 41 which is adapted to bear on its peripheral surface against a similar ring mounted upon the adjacent cylinder 12 for the purpose of regulating the spaced relation of the axes of the two gears when they are in operative positions with respect to each other. The shaft I5 has reduced end portions which are journaled in roller bearings 48 each of which is retained against a shoulder in an aperture it! of the frame ID by means of a. ring 49 secured in place by screws 50. The end of the shaft l5, shown in Fig. 2, is threaded for engagement by a nut 5| and washer 52 and the aperture Iii is closed at the outer side of the nut 5| by means of a cover plate 53 attached to the side frame by screws 54. The other end of the shaft l5 projects through the side frame and is connected to suitable driving mechanism by which the shaft is rotated when the press is in operation.

The cylinder H is secured in adjusted angular position on the shaft I5 by means of a clamp 55 having the form illustrated particularly in Fig. 3. This clamp has a hub portion 55 which fits the shaft l5 and it is split transversely as shown at 55 the slot extending through both sides of the bearing portion 55"- and terminating at one end in an aperture 55 which extends through the clamp and which is adapted to receive a headless screw 56 by which this end of the clamp is secured to the cylinder II, within the hollow interior of the cylinder, the screw engaging threaded apertures in the end wall of the cylinder and in the adjacent bearing ring 41, as

shown in Fig. 2. At the side of the shaft opposite the screw 55, the clamp comprises spaced cars 55 extending parallel to each other on opposite sides of the slot 55 and having apertures 55 therethrough for engagement by a clamping stud 51. The aperture 55 in one of the ears 55 is threaded for engagement by the threaded end of the stud 51 and by tightening this stud, the clamp may be caused to grip the shaft l5 for holding the cylinder Ii against rotation on the shaft. The clamp 55 is held against endwise movement on the shaft and on the screw 56 by means of a collar 58 which is secured on the shaft [5 by means of a' set screw 59. By means of this construction, the clamp 55 may be employed for permitting the cylinder II to be adjusted to any desired angular position on the shaft 15, after which the clamp may be tightened to hold the cylinder in adjusted position, thus making it possible to locate the margin of the impression carried by the plate ii at the desired point with respect to the rubber blanket on the cylinder l2 so that the printed matter will appear in the required location with respect to the paper sheet which is carried by the cylinder l3.

Although one form of the invention has been shown and described by way of illustration, it will be understood that it may be constructed in various other forms coming within the scope of the appended claims.

I claim:

1. The combination in a printing press, of a hollow plate cylinder, a rotatable shaft having said cylinder rotatably mounted thereon, means for rotating said shaft, and a clamp located within and secured to said cylinder, said clamp embracing said shaft for securing said cylinder in adjusted angular position on said shaft, said cylinder having a slot in its outer wall to permit access to said clamp.

2. The combination in a printing press, of a hollow plate cylinder having end walls connected by a cylindrical wall having a slot therein, a rotatable shaft having said cylinder rotatably mounted thereon, means for rotating said shaft, 9. separate split clamp located within said cylinder and embracing said shaft, a pin engaging one end of said clamp for securing it to one of said end walls, and means engaging the other end of said clamp for causing it to grip said shaft and thereby secure said cylinder in adjusted angular position on said shaft.

ALEXANDER T. KOPPE. 

